1,720,976 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Comparison of M-mode and two-dimensional echocardiography in evaluating the left atrium to aorta ratio in cats

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    Assessment of the left atrial (LA) size is crucial in cats with cardiomyopathies because LA dilation, which results from an increased diastolic filling pressure, predisposes towards the development of congestive heart failure and arterial thromboembolism. In addition, LA dilation has been shown to be a negative prognostic factor in cats affected by hypertrophic cardiomyopathy. The aim of this study was to evaluate the agreement between M-mode and two-dimensional (2D) echocardiography in the assessment of LA size in cats. The study was retrospective and observational. Cats with and without heart diseases were included. The LA and aorta (AO) were measured in M-mode and 2D using a standard right parasternal short axis view at the aortic valve level. A left atrium to aorta ratio (LA/AO) >1.5 was considered indicative of LA enlargement. Cohen’s kappa agreement was calculated and Bland- Altman plots were obtained. A total of 188 client-owned cats were included: 104 with heart disease and 84 without heart disease. LA and AO dimensions in M-mode were 13.9 +/- 3.7 mm and 8.7 +/- 1.5 mm, respectively, and in 2D were 14.1 +/- 3.5 mm and 8.8 +/- 1.4 mm, respectively. Bland-Altman plots showed that the mean difference for the evaluation of AO dimensions between 2D and M-mode was 0.1 +/- 1.0 mm and that of LA was 0.1 +/- 1.4 mm. LA/AO measured in 2D and M-mode was 1.6 +/- 0.5 and 1.6 +/- 0.5, respectively, with a median difference between the two methods of 0.0 0.2. Cohen’s kappa yielded a good agreement between the two methods in the interpretation of LA/AO ratio (kappa = 0.760; 95% CI: 0.54–0.99), with 184 agreements out of 188 (97.6%). In conclusion, 2D echocardiography resulted in a slightly higher estimation of the LA and AO diameters in comparison to Mmode, but not for the LA/AO. Because a good agreement was documented between M-mode and 2D evaluation of the LA/AO, the two methods can be used interchangeably to measure this echocardiographic index in cats

    Comparison of two echocardiographic views for evaluating the right pulmonary artery distensibility index in dogs.

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    Echocardiographic evaluation of the right pulmonary artery distensibility index (RPAD index) was recently described as a valuable method for early detection and severity evaluation of pulmonary arterial hypertension in dogs. RPAD index is calculated as the percentage change in diameter of the right pulmonary artery (RPA) between systole and diastole, obtained by M-mode echocardiography from the right parasternal long axis view. The aim of this study was to compare the RPAD index obtained by 2 different echocardiographic views in dogs. The study design was a prospective, multicenter, observational study. Forty-five clientowned dogs from different breeds were included: 31 dogs with heart disease and 14 healthy dogs. Two different right parasternal views, long axis (RPLA) and short axis (RPSA), were used to measure the RPAD index. From the RPLA view (method 1) and RPSA view (method 2) a short axis and a long axis image were respectively optimized for the right pulmonary artery. The RPAD index was calculated by M-mode as the percentage change in diameter of the right pulmonary artery: [(systolic diameter - diastolic diameter)/ systolic diameter]*100. Measurements were done off-line as an average of 5 consecutive cardiac cycles by a single investigator blinded to the dogs’ diagnosis. A Pearson and a Bland-Altman test were used to assess correlation and agreement between the 2 methods, respectively. Intra- and inter-observer measurement variability was quantified by average coefficient of variation (CV). Level of significance was set at P < 0.05. M-mode evaluation of the RPAD index was satisfactorily obtained by both methods in all dogs. Pearson test showed a strong positive linear correlation between the values of RPAD index obtained from both methods (r2 = 0.9346, P < 0.0001). Bland-Altman test showed a good agreement between the 2 methods in estimating RPAD index (bias = 0.51%, SD = 2.96%, 95% limits of agreement = 5.30, 6.33%). The mean difference between the 2 methods was 0.51% (95% confidence interval = 0.35; 1.35). Intra- and inter-observer measurement variability was clinically acceptable (CV<10%).The study showed a good agreement between short axis and long axis M-mode evaluation of RPA. Both methods can be used interchangeably to evaluate RPAD index. Further studies are needed to evaluate the RPAD index in a larger population of healthy dogs and the diagnostic and prognostic role of this echocardiographic parameter in dogs with different types of pulmonary hypertension

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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